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How do the larvae of black soldier flies eat so much, so fast, despite their tiny size? Scientists at Georgia Tech have been studying this "collective feeding" behavior and found that one strategy for maximizing the larvae's feeding rate involves forming maggot "fountains." The scientists described the results in a recent paper in the Journal of the Royal Society Interface, along with an entertaining video showing a swarm of larvae consuming an entire pizza in just two hours.

"This is the first time, as far as I know, that we've really tried to quantify how much they were able to eat, and how they are able to do it," said graduate student and co-author Olga Shishkov, who demonstrated the research on Saturday at the American Association for the Advancement of Science meeting in Washington, DC. It's not the first time she's had fun demonstrating the maggots' hearty appetite in creative ways: last year, she videotaped the critters devouring a heart-shaped donut for Valentine's Day.

Shishkov was drawn to studying the collective dynamics of the creatures because of her background in fluid mechanics. "I was interested in seeing whether I could apply the fluid mechanics techniques I know to study how animals move," she said, with the hope of one day applying the principles she uncovers to robotics.

The lab got its black soldier fly larvae from a startup called Grubbly Farms in Atlanta that raises them as a sustainable source of chicken and fish feed. The larvae eat food waste, especially fruits and vegetables, and are capable of devouring twice their body weight every day. Since humans produce 1.4 billion tons of food waste each year, these larvae are one possible solution for dealing with it. The maggots eat consumer food waste and are fed to the chicken and fish in turn. It's a win-win, all around.

Ten thousand larvae mid-meal in David Hu's lab at Georgia Tech.

O. Shishkov et al.

A close-up image of a black soldier fly larva's mouth.

O. Shishkov et al.

Larvae devour a 16-inch pizza in two hours.

O. Shishkov et al./Grubbly Farms

A pile of larvae is both small and densely packed, making it a bit of a challenge to study. For the feeding experiments, the larvae were placed in a 10-gallon aquarium with cameras placed at the top and bottom to capture the feeding frenzy in action. Then Shishkov and her collaborators used a technique called particle image velocimetry to track the flow of the critters to get an idea of what was really going on inside the hungry horde.

They found that the surface area of whatever food item was offered, like a pizza, limits how many larvae can feed at the same time. Larvae also take frequent breaks from their feeding frenzy and yet block their fellow larvae from moving in on their meal. The other hungry critters get around this behavior by generating fountain-like behavior: "new larvae crawl in from the bottom and are 'pumped' out of the top," the authors write. Shishkov et al. then developed a mathematical model to predict the eating rate.

There's one more practical offshoot from this research. Black fly larvae are raised in giant bins, which can be a problem given their high metabolisms. They can easily overheat while feeding. In the wild, they can just crawl away, but their movement is much more limited in the bins, and an entire colony can easily overheat and die. So larvae farmers air condition the entire warehouse in which the beasties are raised. That's costly and inefficient, which is why Shishkov et al. have also invented an aerating bed—patent pending—that blows cool air through the feeding mass of larvae. This keeps them from over-heating and ensures farmers still get high yields.

I didn't really understand the 'fountain' analogy, so I went ahead and skimmed the article itself. If I understood it correctly, the following is true:

* The larvae are always moving, i.e. researchers usually measure flow, Q.* The larvae fill all possible surface on the food and Q remains about steady until there is no more surface to fill.* The larvae frequently stop eating (or so they think, when a larva isn't in contact with the food, they assume it's not eating, they confirmed this by watching a single larva eat, fascinating stuff about their jaws and stuff), they eat in bursts of 5+-8min and take 5+-10min breaks.* When a larva stops eating, a hungry larva will push it and get its place.* The 'fountain' analogy simply means that given a horizontal piece of food, the larvae want to collectively get access to as much of the surface area as possible, so they pile up, forming a fountain. See Figure 6 of the DOI. No idea why that wasn't in the Ars article, it's the most descriptive image of them all.

Also, turns out around 3500 larvae is a pint (600ml). I'll be sure to remember that the next time I'm in the pub!

one surprise for me was how purposeful and effective was the locomotion.. i haven't spent a lot of time thinking about maggots, but i always envisioned they were little blobs that lie around crying feed me, feed me.. not the case at all.

"The maggots eat consumer food waste and are fed to the chicken and fish in turn. It's a win-win all around."

So we eat chicken and fish that eat larva that eat garbage. I don't feel like much of a winner.

Unless they were hermetically sealed into the coffin, you have probably eaten molecules that were at one time in virtually all of your ancestors' corpses. And given everything they exhaled and otherwise excreted in their lifetimes, you contain a lot more of them consumed by mouth, than you inherited from them through actual nucleobases and proteins. Of course, the same is probably true for all other dead, and many of the living. Fortunately, the transfer tends to be via very small molecules at some point, so the risk of kuru is negligible.

I didn't really understand the 'fountain' analogy, so I went ahead and skimmed the article itself. If I understood it correctly, the following is true:

* The larvae are always moving, i.e. researchers usually measure flow, Q.* The larvae fill all possible surface on the food and Q remains about steady until there is no more surface to fill.* The larvae frequently stop eating (or so they think, when a larva isn't in contact with the food, they assume it's not eating, they confirmed this by watching a single larva eat, fascinating stuff about their jaws and stuff), they eat in bursts of 5+-8min and take 5+-10min breaks.* When a larva stops eating, a hungry larva will push it and get its place.* The 'fountain' analogy simply means that given a horizontal piece of food, the larvae want to collectively get access to as much of the surface area as possible, so they pile up, forming a fountain. See Figure 6 of the DOI. No idea why that wasn't in the Ars article, it's the most descriptive image of them all.

Also, turns out around 3500 larvae is a pint (600ml). I'll be sure to remember that the next time I'm in the pub!

I'm thinking the publican will give a funny look if you ask for a pint of maggots.

"The maggots eat consumer food waste and are fed to the chicken and fish in turn. It's a win-win all around."

So we eat chicken and fish that eat larva that eat garbage. I don't feel like much of a winner.

Unless they were hermetically sealed into the coffin, you have probably eaten molecules that were at one time in virtually all of your ancestors' corpses. And given everything they exhaled and otherwise excreted in their lifetimes, you contain a lot more of them consumed by mouth, than you inherited from them through actual nucleobases and proteins. Of course, the same is probably true for all other dead, and many of the living. Fortunately, the transfer tends to be via very small molecules at some point, so the risk of kuru is negligible.

I made myself extremely unpopular with some fundie Christians who boasted about how they had their children baptised in the actual River Jordan with the actual water that might have been used by actual Jesus. I pointed out that the water cycle means that today's Jordan water is precisely as holy in their terms as any other free flowing water such as rain, and because I am extremely nasty delivered an additional little lecture on how this showed that God treated everybody exactly equally.

"The maggots eat consumer food waste and are fed to the chicken and fish in turn. It's a win-win all around."

So we eat chicken and fish that eat larva that eat garbage. I don't feel like much of a winner.

Unless they were hermetically sealed into the coffin, you have probably eaten molecules that were at one time in virtually all of your ancestors' corpses. And given everything they exhaled and otherwise excreted in their lifetimes, you contain a lot more of them consumed by mouth, than you inherited from them through actual nucleobases and proteins. Of course, the same is probably true for all other dead, and many of the living. Fortunately, the transfer tends to be via very small molecules at some point, so the risk of kuru is negligible.

I made myself extremely unpopular with some fundie Christians who boasted about how they had their children baptised in the actual River Jordan with the actual water that might have been used by actual Jesus. I pointed out that the water cycle means that today's Jordan water is precisely as holy in their terms as any other free flowing water such as rain, and because I am extremely nasty delivered an additional little lecture on how this showed that God treated everybody exactly equally.

And you didn't point out all the horrible parasites and nasties that their baby could have picked up too, you lightweight, you should have put the fear of mother nature up em !!!

I didn't really understand the 'fountain' analogy, so I went ahead and skimmed the article itself. If I understood it correctly, the following is true:

* The larvae are always moving, i.e. researchers usually measure flow, Q.* The larvae fill all possible surface on the food and Q remains about steady until there is no more surface to fill.* The larvae frequently stop eating (or so they think, when a larva isn't in contact with the food, they assume it's not eating, they confirmed this by watching a single larva eat, fascinating stuff about their jaws and stuff), they eat in bursts of 5+-8min and take 5+-10min breaks.* When a larva stops eating, a hungry larva will push it and get its place.* The 'fountain' analogy simply means that given a horizontal piece of food, the larvae want to collectively get access to as much of the surface area as possible, so they pile up, forming a fountain. See Figure 6 of the DOI. No idea why that wasn't in the Ars article, it's the most descriptive image of them all.

Also, turns out around 3500 larvae is a pint (600ml). I'll be sure to remember that the next time I'm in the pub!

Our supplier used to work on 2500 per pint for whiteys, more for pinkies and cased.

Wonderful things maggots, we would literally be up shit creek without them, just imaginhow many millions of tons of waste they must clear up each year all round the world.One of our little local sewage treatment plants used to feed solid lumps of anything that wouldn't break up easily, a day or two of them working it, and most of it was either eaten or was considered to hard to treat at that plant and taken else where, no idea how many millions of maggots involved, but a 20 foot, 8-9 feet deep tank used to be about a third full of maggots, it didn't taken long for them to eat their way through 28 tons of bacon and pork spilled in a nearby truck accident, it was all gone in about 12-14 days...Farmers used to use them for high protein feed instead of fish etc, cooked up in giant pots, mixed up with other food waste and fed to pigs...

"The maggots eat consumer food waste and are fed to the chicken and fish in turn. It's a win-win all around."

So we eat chicken and fish that eat larva that eat garbage. I don't feel like much of a winner.

I don't see the problem. Chickens naturally eat these critters, among other things, as others have said. This is just doing it at scale instead of making the chickens find them one by one. Hell, anyone who eats shrimp, prawns, crayfish, lobsters, or crabs is cutting out the middleman, frankly, and those are widely considered friggin' delicacies!